“Appropriate measures” will be put in place to prevent a repeat of a dramatic “dust devil” that startled onlookers in Manchester over the weekend.
The swirling 30ft (10m) column of dust and debris was pictured beating a path across Great Ancoats Street in the city centre on Saturday afternoon.
Similar in appearance to a mini-tornado, the phenomenon was caused by contrasts in temperature causing air to rotate.
Manchester City Council said the dust devil originated from the Central Retail Park building site, a vacant swathe of open land which is being redeveloped into a civil service office complex.
The authority said: “The meteorological conditions required to create a so-called dust devil are uncommon in urban areas and so it’s rare that a site is affected in the way we saw over the weekend.
“However, dust control is a consideration for any development, and we’ll ensure the developer takes appropriate measures to manage the site throughout the construction period.”
One eyewitness said he “froze” when she saw the column of dust spiralling towards him.
Violinist Adam Riding, 30, said: “It was the most amazing thing.
“I’ve never seen anything like that, and to witness it in the city on really not a very windy day.
“It was like this wind tunnel between buildings had created this mini-vortex. It was bizarre.”
Met Office meteorologist Alan Goodman said dust devils were a “rare occurrence” in the UK.
He said: “The ground was very, very warm. When you get this very warm air near the ground it will rise.
“And then if you just get it right, the air starts to rush in from the sides and you get this sort of rotation motion.”
The Government Property Agency, which is redeveloping the Central Retail Park site, said the dust devil was the result of “exceptional meteorological conditions”.
It added: “In response to this, the contractors currently managing the site have taken the additional steps of bringing in a road sweeper and a towable water bowser to reduce the likelihood of dust being blown from this plot if unusual weather patterns continue.”
